IPB

Welcome Guest ( Log In | Register )

19 Pages V  < 1 2 3 4 5 > »   
Reply to this topicStart new topic
KBO encounters
nprev
post Apr 15 2010, 09:32 AM
Post #31


Senior Member
****

Group: Moderator
Posts: 7144
Joined: 8-December 05
From: Los Angeles
Member No.: 602



Actually, Alan said in this post that the search won't start till next year.


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post
Alan Stern
post Apr 15 2010, 12:18 PM
Post #32


Member
***

Group: Members
Posts: 464
Joined: 19-February 05
Member No.: 173



QUOTE (Vultur @ Apr 15 2010, 10:15 AM) *
The first post in this thread says the search would start in 2010 - has it started yet, or will it be later this year?


Our best imager, LORRI, can resolve the size of an object from roughly 10^5 object diameters away. So for a 100 km object, for example, we have to be w/i 10^7 km just to resolved it; if you want crude shape information, cut that to 10^6 diameters, and if you want "geology," well, better come to approx 30,000 diameters or better. The point here is Crantor and other distant flybys don't yield much of use, so we have not expended effort on them.

As to our KBO search, John Spencer is leading the organizational effort to recruit search teams; Andrew Steffl is helping John. Our plan is to conduct the search in 2011 and 2012, though Scott Shepard at least has already begun.

-Alan
Go to the top of the page
 
+Quote Post
Greg Hullender
post Apr 15 2010, 04:58 PM
Post #33


Senior Member
****

Group: Members
Posts: 1010
Joined: 29-November 05
From: Seattle, WA, USA
Member No.: 590



Yeah, I think the last few times we've asked this question (maybe we need an FAQ section for each long-term mission) the answer was "not until we're past the orbit of Uranus."

--Greg
Go to the top of the page
 
+Quote Post
illexsquid
post Apr 27 2010, 06:11 PM
Post #34


Newbie
*

Group: Members
Posts: 17
Joined: 29-May 08
From: Seattle, USA
Member No.: 4162



QUOTE (Alan Stern @ Apr 15 2010, 04:18 AM) *
Our best imager, LORRI, can resolve the size of an object from roughly 10^5 object diameters away. So for a 100 km object, for example, we have to be w/i 10^7 km just to resolved it; if you want crude shape information, cut that to 10^6 diameters, and if you want "geology," well, better come to approx 30,000 diameters or better.

Alan, thanks for the info, but I'm a little confused... I assume that for crude shape information, you mean cut the maximum distance to 106 kilometers, since 106 diameters would be 108 kilometers. But which do you mean for the "geology" figure? 30,000 diameters would be 3 million kilometers for our theoretical 100 km object, which is tough enough, but 30,000 kilometers is more or less a bullseye: better targeting than even Apophis will manage smile.gif . It seems to me you could get at least some worthwhile surface-feature resolution at a greater distance than that. The famous LORRI images of Tvashtar's plume resolved fine details at 2.5 million km. On the other hand, I know that spacecraft (and ground) resources are limited, and you have to be sure you're getting enough meaningful data for any expenditure. Could you give any hints as to when you think it might be worthwhile to observe during one of these flybys?

Go to the top of the page
 
+Quote Post
Gsnorgathon
post Apr 28 2010, 05:55 PM
Post #35


Member
***

Group: Members
Posts: 251
Joined: 23-January 05
From: Seattle, WA
Member No.: 156



The Tvashtar plume images were taken a lot closer to the sun than any KBO images will be. I imagine blurring due to longer exposure times would reduce resolution at comparable distances.
Go to the top of the page
 
+Quote Post
john_s
post Apr 28 2010, 07:36 PM
Post #36


Member
***

Group: Members
Posts: 534
Joined: 3-December 04
From: Boulder, Colorado, USA
Member No.: 117



I'll chip in here. Alan was talking about science at Centaurs that we might fly past on our way to Pluto- none of those will get close enough to be resolved. For the KBO target(s) beyond Pluto, we will deliberately target to get within a few tens of thousands of kilometers or closer- from 20,000 km, for instance, we would get 500 pixels across a 50 km KBO- sufficient to do some serious geology. LORRI can get well-exposed, unsmeared, images at Pluto's distance from the sun (it was designed to do that, of course), and while illumination conditions will be more challenging further out in the Kuiper Belt, there's enough performance margin that we expect to be able to do the same there.

At Crantor's distance, a LORRI pixel is 2000 km across, much bigger than Crantor itself. So there's no hope of getting any shape information.

And to make sure no-one is still confused on this point, we will not be searching for KBOs with NH itself- huge ground-based telescopes with wide-field imagers can do that much better, even though they're stuck at 1 AU.

John
Go to the top of the page
 
+Quote Post
john_s
post Feb 22 2011, 10:55 PM
Post #37


Member
***

Group: Members
Posts: 534
Joined: 3-December 04
From: Boulder, Colorado, USA
Member No.: 117



Talking of KBOs, here's a heads-up that YOU can probably help us to find Kuiper Belt objects for New Horizons to fly by after Pluto, starting in a month or two. We're working with the Zooniverse folks to set up a "KBO Zoo" where you will be able to help us identify moving objects (i.e. potential KBOs) in the Milky Way star fields that we'll be imaging with the Subaru, Magellan, and Canada-France-Hawaii telescopes this summer. Details once the site is up and running.

John

Go to the top of the page
 
+Quote Post
Astro0
post Feb 22 2011, 11:01 PM
Post #38


Senior Member
****

Group: Admin
Posts: 2877
Joined: 21-December 05
From: Canberra, Australia
Member No.: 615



smile.gif If we find it, can we name it?! I always thought that "Astro0's Orb" had a nice ring to it! laugh.gif
Go to the top of the page
 
+Quote Post
stevesliva
post Feb 22 2011, 11:54 PM
Post #39


Senior Member
****

Group: Members
Posts: 1174
Joined: 14-October 05
From: Seattle
Member No.: 530



QUOTE (john_s @ Feb 22 2011, 06:55 PM) *
We're working with the Zooniverse folks to set up a "KBO Zoo" where you will be able to help us identify moving objects (i.e. potential KBOs) in the Milky Way star fields that we'll be imaging


Sweet!
Go to the top of the page
 
+Quote Post
nprev
post Feb 23 2011, 01:10 AM
Post #40


Senior Member
****

Group: Moderator
Posts: 7144
Joined: 8-December 05
From: Los Angeles
Member No.: 602



THAT is a rockin' piece of citizen science outreach, John! smile.gif Very much looking forward to it!


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post
hendric
post Feb 23 2011, 02:54 PM
Post #41


Director of Galilean Photography
***

Group: Members
Posts: 714
Joined: 15-July 04
From: Austin, TX
Member No.: 93



John,
That's great news, can't wait to participate in the search for targets!


--------------------
Space Enthusiast Richard Hendricks
--
"The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke
Mother Nature is the final inspector of all quality.
Go to the top of the page
 
+Quote Post
MahFL
post Apr 20 2011, 02:59 PM
Post #42


Forum Contributor
****

Group: Members
Posts: 1030
Joined: 8-February 04
From: North East Florida, USA.
Member No.: 11



The Search for KBO's to begin.
Go to the top of the page
 
+Quote Post
john_s
post Apr 20 2011, 03:17 PM
Post #43


Member
***

Group: Members
Posts: 534
Joined: 3-December 04
From: Boulder, Colorado, USA
Member No.: 117



Look for another release in a few weeks, describing how you can help us sift through all those images.

John
Go to the top of the page
 
+Quote Post
dilo
post Apr 20 2011, 03:47 PM
Post #44


Senior Member
****

Group: Members
Posts: 2492
Joined: 15-January 05
From: center Italy
Member No.: 150



QUOTE (john_s @ Apr 20 2011, 03:17 PM) *
Look for another release in a few weeks, describing how you can help us sift through all those images.


Great, I cannot wait!!! rolleyes.gif


--------------------
I always think before posting! - Marco -
Go to the top of the page
 
+Quote Post
tfisher
post May 8 2011, 03:12 AM
Post #45


Member
***

Group: Members
Posts: 200
Joined: 29-June 05
Member No.: 421



QUOTE (john_s @ Feb 22 2011, 05:55 PM) *
Talking of KBOs, here's a heads-up that YOU can probably help us to find Kuiper Belt objects for New Horizons to fly by after Pluto, starting in a month or two.


Any update on this?
Go to the top of the page
 
+Quote Post

19 Pages V  < 1 2 3 4 5 > » 
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 29th November 2014 - 02:24 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.